A cooking device is one of kitchen utensils which heat and cook food to an edible state. The cooking device may be classified into an electric cooking device and a gas cooking device depending on a type of a heating source.
A heater which receives electric power and generates heat may be installed at the electric cooking device, and a burner which burns a supplied gas and generates the heat by a flame may be installed at the gas cooking device.
Also, according to a type thereof, the cooking device may be classified into an oven type which heats the food in a state in which the food is accommodated in a cooking chamber providing a space for cooking the food, and a range type which heats a cooking container, in which the food is accommodated, at an open space.
Recently, a multipurpose type cooking device which satisfies users' tastes while enabling a variety of foods to be cooked, i.e., an oven range type cooking device in which the oven type and the range type are combined is provided.
And various types of heating sources for heating the food may be installed at the cooking device. A magnetron which applies microwaves to the accommodated food and heats the food, a heater which converts electric energy of the supplied electric power into heat energy and heats the accommodated food, or a burner which generates the heat by the flame generated by burning the supplied gas may be installed as the heating source.
Recently, a cooking device in which two or more heating sources are installed to cook the variety of foods is provided, and another cooking device type in which the magnetron and the heater are installed or the heater and the burner are installed may be provided.
Meanwhile, in Korean Patent Publication No. 2007-0038653 (hereinafter, referred to as a “first prior art document”), there is disclosed an invention related to a heater which may be optimally used in a cooking device. In the first prior art document, there is disclosed a carbon heater including a carbon filament which has a predetermined thermal expansion coefficient and generates heat by applying the electric power thereto; a heat generating member which has a thermal expansion coefficient different from that of the carbon filament and is mutually supported by the carbon filament; and a tube which is spaced apart from the carbon filament and the heat generating member while the carbon filament and the heat generating member are sealingly inserted therein.
Also, in Korean U.M. Registration No. 20-0399008 (hereinafter, referred to as a “second prior art document”), there is disclosed an invention related to an electric oven using a carbon heater, which is manufactured using the carbon heater formed of a porous basalt fiber to remarkably enhance a heat generating area, and thus capable of being manufactured to have a large capacity while generating high temperature heat and also to be beneficial to a human body.
The second prior art document describes a configuration of the electric oven using the carbon heater, which includes a heater stand which is manufactured in a quadrangular frame shape, a plurality of carbon heaters which are installed at a frame of the heater stand at regular intervals, and a fire resisting wall which is installed to cover an outside of the heater stand and the carbon heater and thus to insulate internal heat.
As described in the first and second prior art documents, recently, a technique which increases radiant heat through various kinds of heaters and various types of structures, and thus reduces a cooking time of the food has been continuously developed.
And a technique which enables a variety of foods to be cooked by installing a plurality of heating sources to cook the variety of foods and heating the foods has been also continuously developed.
Since the plurality of heating sources are installed, a cooking operation is performed by heating the foods according to a property of each of the heating sources, and a cooking chamber should be formed to be appropriate to the property of each of the heating sources.
Like this, it may be confirmed that the heating source is an important factor in cooking the food, and a configuration which enhances a calorific value of the radiant heat or the like is important for reducing the cooking time of the food.